Fibre composition of human hand and arm muscles.

The fibre composition of 5 hand and 3 arm muscles were investigated by histochemical methods. The hand muscles of the dominant side (right side by the right-handed and left side by the left-handed persons) had a significantly higher amount of type 2 fibre than type 1 fibre. In the same subjects the fibre composition of the 3 investigated arm muscles were practically the same on the dominant and on the non-dominant side. It is suggested that the different movements of the dominant hand causes the difference in the fibre ratio of the hand muscles, while the different mechanical demands did not influence the composition of the arm muscles.